Mike Rees, senior Investigating officer for the covert operation, said: “Yesterday's activity sends a strong message out to anyone who sees Wiltshire as an easy target or Wiltshire Police as a soft touch.

“We will not tolerate anyone setting up a drugs network in Swindon or Wiltshire and we will put all of our resources into bringing those involved to justice.

"As predicted, we will continue to locate and arrest those outstanding suspects in the coming days and will not rest until we have completed this task.

“The operation was the culmination of over a year’s hard work from our undercover officers who are putting themselves at risk by associating with known criminals, often without any protection, to build up the intelligence we need for an operation like this.

“I would like to pay my personal respects to these officers – I have total admiration for what they do.”

Raids in Swindon were carried out in the Manchester Road area and six arrest arrests were made as part of the London phase of the operation.

Following the operation Wiltshire Police seized approximately £50,000 worth of illegal tobacco from a house in Melksham, last night.

Operation Harness is a long-term collaborative project tackling issues which affect communities, involving all police officers and staff over a number of organised days of action throughout the year.

Detective chief inspector Craig Holden, of Wiltshire Police, said: “This activity is just one of a number of tactics we use to disrupt and dismantle Dangerous Drugs Networks across our county.

“As a result of this day of action alone, we anticipate that we have significantly disrupted or completely dismantled more than 15 of these networks operating in Swindon.

“Wiltshire Police have a dedicated team to specifically tackle these networks and we will relentlessly pursue those who are responsible for supplying drugs in our communities.”